Coil construction



N. MCKINNEY COIL CONSTRUCTION Nov. 28, 1950 Filed Aug. 22, 1946 1.4., Il s INVENToR /VoPMn/v Mc K//wvs Y ATTORNEY Patented Nov. 28, 1950 COIL CONSTRUCTION Norman McKinney, Elkins Park, Pa., assignor of one-half to Joseph F. Ebert, doing business as Ebert Engineering and Manufacturing Com- Dany Application August 22, 1946, Serial No. 692,334

4 Claims.

The present invention relates to a coil and a method of constructing the same and has for a particular object the provision of a novel coil construction which, while simple, may nevertheless be of great rigidity and durability as well as having other objectives stated hereinbelow.

The invention is particularly adapted to coils manufactured by what are known in the trade as universal winding machines wherein enameled copper wire is fed through a travis to form layers of wire, while at the same time through a second travis which moves transversely at a relativey much higher speed than the first travis, cotton thread is fed in order to interweave it with the Wire and, hence, give a high dielectric insulation to the finished coil.

When coils of this character have'been wound to the required number of turns, the machine is stopped and insulating material is laid upon the same and the terminals of the present invention are then placed in proper position and soldered to the ends of the coil. The machine is again started, feeding thread only and securely binding the terminals. When sufficient thread is laid upon the coil, the machine is again stopped and the assembled coil is then impregnated with varnish or other plastic material and then heat treated to bind the same more securely into a compact mass and give a more durable finish to the completed product.

It will be apparent that in using a machine of the type herein described, it is essential that no interference with the thread feed may take place and this comprises one object of the invention, namely the shaping and mounting of terminals in such manner that no interference is had between them and the thread in the course of winding.

A further object of the invention is the provision of a novel means for locking the terminals usually associated with such devices in such manner that they will be secure from loosening.

A further object of the invention is the provision of novel means for electrically insulating and physically protecting the windings of a coil.

A further object of the invention is the provision of easy means of access to the terminals of a completed coil construction.

Still another object of the invention is the provision of a novel method of winding and attachment of terminals to an electric coil.

A further object of the invention is the provision of terminals of such formation as to clear the framework ordinarily associated with a coil construction.

Other and further objects of the invention will become apparent from a reading of the following specication taken in conjunction with the drawings.

In the drawings:

Figure 1 is a perspective view, partly broken away, showing an embodiment of the invention, and

Figure 2 is a sectional view taken along line 2 2 of Figure 1.

Referring more particularly to the drawings. there is shown therein a c'oil having a central hollow cylindrical tube I0 of dielectric material upon which is wound magnet wire intermingled with cotton thread II in the customary manner, that is, by means of a universal winding machine. The two ends I3 of the wire are soldered or otherwise electrically attached to the terminal pieces I4 and I5, respectively.

Over the wound wire and thread II is placed a covering 9 of paper and it will be seen that the terminal pieces I4 and I5 lie with their extending ilat leg portions generally in a vertical plane upon the paper 9 substantially parallel to the longitudinal axis of tube I0 and are provided with offset outwardly and downwardly extending feet I6 and I'I,' respectively, having the customary threaded openings I8 and I9, respectively, for the reception of screws I8 and I9', respectively.

Upon the substantially fiat leg portions of the terminals I4 and I5 is wound a layer of thread 20 extending over the entire length of the coil and completely covering the leg portions of the two terminals. The entire coil, in the final form, may be impregnated or coated with varnish, shelllac or like plastic material and then baked to form a compact mass.

A cover 2| is shown glued or otherwise similarly attached to the top of the completed coil.

It will be apparent that by the winding of the thread 20 extending entirely over the flat leg portions of the terminals that great rigidity is imparted to such terminals and that, in the completed device, such terminals are substantially integral with the remainder of the device and that, since the feet of the terminals extend outwardly from the coil during the winding process, they may not interfere in any manner with the thread as it is wound throughout the entire length of the coil.

It will also be seen that the terminals are so bent in an outward direction that they will have suitable and suilicient clearance from the metal frame upon which such coils are customarily mounted and that lead wires may be connected 3 to the feet i and l1 very readily because of the easy accessibility provided by this construction.

While but one form of the invention has been shown and described herein, it will be readily apparent to the skilled in the art that many minor modiilcations may be made without departing from the spirit oi the invention or the scope of the appended claims.

What is claimed is:

l. A magnetic coil construction comprising a central insulating member. a winding o! magnet wire surrounding said central insulating member. said magnet wire having insulation between the turns thereof to insulate one turn from another, said magnet wire having two ends. a covering of insulating material surrounding the magnet wire and insulation, terminal pieces of conductive material connected respectively to the ends of the magnet wire and resting against the insulating covering and spaced from each other and a layer of insulating threads surrounding and drawn over the insulating covering and over the terminal pieces to hold the insulating covering andthe terminal pieces in place upon the magnetic winding and the terminal pieces spaced from one another.

2. A magnetic coil construction comprising a central insulating member, a winding of magnet wire surrounding said central insulating member, said magnet wire having insulation between the turns thereof to insulate one turn from another, said magnet wire having two ends, a covering of insulating material surrounding the magnet wire and insulation, terminal pieces of conductive material connected respectively to the ends of the wire resting against the insulating covering and spaced from each other and a layer of insulating threads surrounding and drawn over the insulating covering and extending over the terminal pieces to hold the insulating covering and the terminal pieces in place upon the masnetic winding and the terminal pieces spaced from one another, and said threaded layer being treated with insulating material to hold the insulating and securing threads and to provide an integral mass including the covering threads and tuelminal pieces surrounding the magnetic wind- 3. A magnetic coil as in claim 1 in which each of the terminal pieces comprises a portion extending axially and radially beyond the coil.

4. A magnetic coil as in claim 2 in which each of the terminal pieces comprises a portion extending axially and radially beyond the coil.

NORMAN MCKINNEY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Milton Dec. 30, 1919 Freeland Dec. 19, 1933 Branson Aug. 24, 1937 Franz Apr. 11, 1939 DEntremont May 27, 1941 Number 

